Vehicles with electrically variable transmissions are commonly driven in part by the transmission including the associated battery and motor/generators. Excess energy from the vehicle is used to regenerate the stored power of the battery. For example, the energy dissipated during braking is used to regenerate the battery charge.
However, recharging a battery too quickly may have undesirable side effects, such as increasing the battery temperature above a desired operational range and overcharging the battery. Overcharging the battery may result in uneven drive of the vehicle and decreased fuel efficiency. Often, the battery can act as a buffer during the recharging to maintain an even drive effect on the vehicle. However, if the battery is already near capacity or hot, the recharging of the battery may occur too quickly for the battery to provide a buffering effect. This especially occurs during events that create large amounts of power for recharging the battery, such as braking. The desired amount of regeneration of the battery depends on several factors including the temperature of the battery, the current amount of charge stored by the battery, and the amount of charging power available at a given time.